This application is based upon and claims the benefit of priority of Japanese Patent Application No. 2001-242944 filed on Aug. 9, 2001, the content of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a headlamp cleaner for injecting washer liquid in order to clean vehicle headlamps and an injection control method applicable to the headlamp cleaner.
2. Description of Related Art
A headlamp cleaner is known as a device for cleaning vehicle headlamps at a driver""s choice, when the headlamps are dirty, upon actuating a switch provided near a driver""s seat. The headlamp cleaner is composed of a pair of injection nozzles which are arranged to face positions where the headlamps are provided on the left and right sides of the vehicle and from which washer liquid is injected toward the headlamps, a tank disposed in an engine room for storing washer liquid and a pump apparatus housed in the tank for delivering washer liquid under pressure through piping hoses to the respective injection nozzles.
When the driver actuates the switch at hand and the pump apparatus is operated, the washer liquid is supplied under pressure to the injection nozzles from the pump apparatus so that the washer liquid is sprayed simultaneously to both of the headlamps corresponding to the respective injection nozzles. Since the headlamps are cleaned only by injecting the pressurized washer liquid and a wiper device is not necessary for their cleaning, the structure of the headlamp cleaner is relatively simple.
However, in the conventional headlamp cleaner, the pump apparatus has to deliver the washer liquid whose discharge pressure and discharge amount are relatively high because not only the headlamps are cleaned only by washer liquid injection but also the washer liquid is injected at the same time from the pair of right-hand and left-hand injection nozzles. Accordingly, the conventional headlamp cleaner requires the pump apparatus whose body is relatively large and which is provided for a purpose of its own exclusive use.
The larger body pump apparatus as mentioned above causes a difficulty on installing the headlamp cleaner in the engine room where many component parts are arranged (due to limitation of its installation space) and, further, is not always commonly applicable to a variety of models so that a cost of the headlamp cleaner is higher.
An object of the present invention is to provide a headlamp cleaner having a compact pump apparatus for supplying washer liquid to first and second injection nozzles arranged to face toward positions where headlamps are provided on left and right sides of a vehicle.
Another object is to provide a method of controlling a washer liquid injection from the headlamp cleaner.
To achieve the above objects, in a headlamp cleaner for injecting washer liquid to headlamps of a vehicle provided respectively on a driver seat side and on a passenger front seat side, one of first and second injection nozzles is positioned near and injects the washer liquid to one of the headlamps and the other thereof is positioned near and injects the washer liquid to the other of the headlamps. A pump apparatus, which has an input port communicating with a tank in which the washer liquid is stored and first and second discharge ports communicating with the first and second injection nozzles, respectively, is provided with not only a pump for delivering under pressure the washer liquid sucked from the tank through the intake port to the first and second discharge ports but also injection nozzle change over means operative based on signals from an injection control unit to cause a first selective flow of the washer liquid from the pump only to one of the first and second injection nozzles through one of the first and second discharge ports and, then, switch the first selective flow to a second selective flow of the washer liquid from the pump only to the other of the first and second injection nozzles through the other of the first and second discharge ports.
With the headlamp cleaner mentioned above, since the washer liquid is supplied to the selected one of the first and second injection nozzles due to the injection nozzle change over means, the first and second injection nozzles do not inject the washer liquid at the same time to the headlamps so that an amount per unit time of the washer liquid discharged from the pump is relatively small, resulting in making the pump apparatus more compact.
It is preferable that the signals generated by the injection control unit govern the pump apparatus to execute, as an injection cycle, a first step of injecting the washer liquid only from the first injection nozzle for a first preset time period and, then, a second step of injecting the washer liquid only from the second injection nozzle for a second preset time period. More preferably, the injection cycle is executed at least a twice. In this case, each of the first and second preset time periods in the former injection cycle may be shorter than that in the latter injection cycle.
The washer liquid primarily injected to one of the headlamps at the first step of the first cycle gives moisture to the one of the headlamps so that the washer liquid injected to the one of the headlamps at the first step of the second cycle effectively cleans dirt, since the dirt is apt to come off the surface of the one of the headlamps and rise in the washer liquid during a time period when the washer liquid is injected to the other of the headlamps at the second step of the first cycle. In particular, the injection time period (the first and second preset time periods) of the first cycle for giving moisture to the respective headlamps to cause the dirt to rise in the washer liquid is shorter than the injection time period of the second cycle so that cleaning (injection) time is shorter and consumption of the washer liquid is smaller as a whole, resulting in achieving higher cleaning efficiency.
It is preferable that the first injection nozzle is positioned near the headlamp on the driver seat side and the second injection nozzle is positioned near the headlamp on the passenger front seat side. In this case, preferably, the first preset time period is longer than the second preset time period. If the headlamp on the driver seat side is cleaned first with priority over or more intensively than the headlamp on the passenger front seat side, an intensity of illumination of the headlamp on the driver seat side is recovered earlier or easily than that of the headlamp on the passenger front seat side, which gives an advantage that driver""s visibility is secured at an earlier time.
As one of the embodiment, the pump apparatus mentioned above may have the pump (preferably, an electric motor having an impeller fixed to a rotating axis thereof) driven based on the signals from the injection control unit to rotate in a normal direction and, then, switched to rotate in a reverse direction, the intake port having first and second intake ports, and first and second valves. In this case, when the pump is rotated in the normal direction, pressure of the washer liquid sucked from the second intake port and pressurized by the pump causes the first valve to move so as to close the first intake port and open the first discharge port in a state that the second valve closes the second discharge port, and, when the pump is rotated in the reverse direction, pressure of the washer liquid sucked from the first intake port and pressurized by the pump causes the second valve to move so as to close the second intake port and open the second discharge port in a state that the first valve closes the first discharge port. Accordingly, the first and second valves in cooperation with the pump constitute the injection nozzle change over means.
As another embodiment, the pump apparatus may have, as the injection nozzle change over means, an electromagnetic valve operative based on the signals from the injection control unit to cause a first state that the first discharge port is opened and the second discharge port is closed and, then, switch the first state to a second state that the first discharge port is closed and the second discharge port is opened.
Further, as a modification, the injection nozzle change over means may be first and second electromagnetic valves operative independently of each other based on the signals from the injection control unit to cause a first state that the first discharge port is opened by the first electromagnetic valve and the second discharge port is closed by the second magnetic valve and, then, switch the first state to a second state that the first discharge port is closed by the first magnetic valve and the second discharge port is opened by the second magnetic valve. It is preferable that the first and second electromagnetic valves are positioned in vicinity of and upstream of the first and second injection nozzles.